std::atan2

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Defined in header <cmath>
float       atan2( float y, float x );
double      atan2( double y, double x );
long double atan2( long double y, long double x );

Computes the inverse tangent of y/x using the signs of arguments to correctly determine quadrant.

[edit] Parameters

x, y

-

floating point value

[edit] Return value

arc tangent of y/x in radians in the range of [-π; π] radians.

[edit] See also

atan	computes arc tangent (arctan(x)) (function)
asin	computes arc sine (arcsin(x)) (function)
acos	computes arc cosine (arccos(x)) (function)
tan	computes tangent (tan(x)) (function)